(a) Field of the Invention
The present invention relates to a liquid-crystal display panel used in a liquid-crystal display device.
(b) Description of the Related Art
A liquid-crystal display panel is used in a liquid-crystal display device of a portable computer, for example, for providing a color or monochrome image. Referring to FIGS. 1 and 2 showing a top plan view and a cross-sectional view, respectively, of a conventional liquid-crystal display panel, liquid crystal 407 is sandwiched between a pair of transparent oblong substrates 401 and 403, on which a plurality of transparent pixel electrodes 402 arranged in a matrix and a transparent common electrode 404 are disposed, respectively.
A plurality of strip electrodes including scanning electrodes and signal electrodes are disposed on the lower substrate 401 for driving the pixel electrodes 402. A transfer electrode 409 is disposed at each corner region of the substrates 401 and 403 for providing conduction between the electrodes disposed on both the substrates 401 and 403. The peripheries of the lower substrate 401 and upper substrate 403 are bonded together by an adhesive 406 for sealing the liquid crystal 407, which is introduced in the space between the substrates 401 and 403 through a liquid-crystal inlet 410 disposed at a gap of the adhesive 406.
The inlet 410 is finally closed after introduction of the liquid crystal 407 by using a sealant or insulating paste. The adhesive 406 is selected from an organic adhesive and extends substantially along the oblong edge of the substrates 401 and 403. Each corner of the oblong substrates 401 and 403 is short-cut by an oblique line of the adhesive 406 for circumventing the location of the transfer electrode 409.
The circumvention of the transfer electrode 409 necessitates provision of a space between the peripheral adhesive 406 and transfer electrode 409 and a space between the peripheral adhesive 406 and the pixel electrodes 402, which retards reduction of the area for the liquid-crystal display panel.
In view of the above, Patent Publication No. JP-A-4(1992)-17228 proposes use of a conductive paste for the peripheral adhesive 406 for conduction between the electrodes on both the substrates instead of the transfer electrode 409. This method, however, sometimes involves a short-circuit failure in the electrodes in the vicinity of the peripheral adhesive.
Patent Publication No. JP-A-2(1990)-302730 proposes a transfer electrode implemented by a part of peripheral adhesive which contains conductive spacers therein to provide conduction between the electrodes on both the substrates. In this technique, however, both printing steps are needed for peripheral adhesive and transfer electrode, both of which request printing boards therefor and accordingly increase fabrication steps and raise fabrication costs.